assuming you mean the credencial, non-Spaniards normally get one from their local Jacobean association, in your case in Sweden, or when they cross into Spain, e.g. at Roncesvalles. There is normally no charge for this. If you're not doing either of these, you can get one from the Amics in Barcelona
http://www.amicsdelspelegrins.org/ipresentacio.htm
There's an online form, or, probably better if you're in Barcelona, go round to their office. They might ask you to become a member or give a donation before they'll give you one. Either way, these are/should be valid at all albergues anywhere in Spain (or at pilgrim hostels in other countries). AIUI, discussions are under way for creating a standardised credencial throughout Europe.